Acetabular Bone Deficiency Research Articles

Cementless Acetabular Reconstruction for Arthropathy in Old Acetabular Fractures.

This study was conducted to identify the factors influencing mechanical failure of cementless acetabular reconstruction for arthropathy after operative treatment of acetabular fractures. Fifty-six patients (56 hips) undergoing cementless total hip arthroplasty were enrolled and followed for a mean of 120 months (range, 60-180 months). The 10-year survival rate, with mechanical failure (radiographic loosening or revision due to aseptic loosening) as the endpoint, was analyzed with respect to sex, age, body mass index (BMI), acetabular bone deficiency, sclerotic changes to the acetabulum, and use of the Trabecular Metal (TM) cup (Zimmer, Inc, Warsaw, Indiana). Mean 10-year survival rates of the acetabular component were as follows: 80% (range, 65%-96%) in males and 100% in females (P=.032); 77% (range, 60%-95%) in patients younger than 50 years and 91% (range, 82%-100%) in older patients (P=.027); 88% (range, 78%-98%) in patients with a BMI less than 30 kg/m(2) and 81% (range, 74%-89%) in patients with a BMI of 30 kg/m(2) or higher (P=.068); 54% (range, 32%-76%) in patients manifesting large acetabular deficiency and 90% (range, 78%-100%) in the remaining patients (P<.001); 78% (range, 65%-91%) in patients with the presence of sclerotic acetabulum and 92% (range, 86%-100%) in patients with the absence of sclerotic acetabulum (P=.022); and 82% (range, 73%-100%) in patients who received a conventional shell and 100% in patients who received the TM cup (P=.039). Male sex, age younger than 50 years, large acetabular deficiency, and sclerotic changes of the acetabulum were significant factors contributing to the mechanical failure of cementless acetabular reconstruction performed for old acetabular fractures treated with open reduction and internal fixation. Use of the TM cup seemed able to prolong the endurance of the acetabular component in the subsequent reconstruction.

Long-Term Outcome of Acetabular Reconstruction Using a Kerboull-Type Acetabular Reinforcement Device with Hydroxyapetite Granule and Structural Autograft for AAOS type II and III Acetabular Defects

We evaluated the clinical results of the reconstruction of acetabular bone deficiency using hydroxyapatite (HA) granules and structural autografts supported by a Kerboull-type acetabular reinforcement device at a minimum of 10 years follow-up. Between 1993 and 2003, 40 consecutive THA revisions were performed in 37 patients with a mean age of 66.4 years. The mean follow-up period was 12.8 years. Radiologically, 5 hips failed, of which 2 were revised. The survival rate of the acetabular component at 10 years was 100% in type II defects and 94.9% in the type III defects, using acetabular revision for loosening as the end point. Acetabular reconstruction with HA granules, structural autografts and a Kerboull-type acetabular reinforcement device provided satisfactory clinical and radiological results at 12.8 years postoperatively.

The midterm and long-term effects of acetabular roof ring and Burch-Schneider anti-protusio cages in acetabular revisions for patients with acetabular bone deficiency.

The purpose of this study was to investigate the mid-term and long-term effects of the acetabular roof ring (ARR) and Burch-Schneider anti-protrusio cage (BSAPC) in acetabular revision for patients with acetabular bone deficiency and acetabular component loosening. Between 1988 and 2007, ARR revisions were performed in 51 patients (25 women; average age: 46.9 years) and BSAPC in 18 patients (16 women; average age: 62.1 years). Grafts were used in all revisions. The patients were evaluated retrospectively. The bone defects were classified according to the classification of the American Academy of Orthopaedic Surgeons (AAOS). Harris Hip Score (HHS) was used for clinical evaluation. Radiolucent lines, implant sizes, osseointegration, and heterotopic ossification in the 3 regions defined by DeLee and Charnley were evaluated radiologically. The success rate of ARR revisions after an average follow-up of 8.93±4.10 years (range: 4-23 years) was 87.9%, and the cumulative survival rate at year 10 postoperatively was 91%. Average HHS score increased to 83.70±8.98 postoperatively, from 40.10±2.49 preoperatively (p<0.01). The success rate of BSAPC revisions after an average follow-up of 7.06±2.39 years (range: 4-12 years) was 83.3%, and the cumulative survival rate was 78%. Average HHS score increased from 42.55 preoperatively to 73.86 postoperatively (p<0.01). All failures of ARR revisions occurred in type 3 defects (p<0.05). In 40 of the 47 patients in which an allograft was used, osseointegration occurred. No statistically significant difference was found between the increase in HHS scores of patients who underwent femoral component revision with acetabular revision and those who did not (p=0.06). Patients who underwent more than 1 revision had statistically significantly higher failure rates in comparison to patients undergoing revision for the first time (p=0.008). The mid-term and long-term results of the use of ARR and BSAPC with allografts in bone deficient acetabular revisions are satisfactory. The implants facilitate graft osseointegration, increase the bone stock, and make future revisions easier. ARR should be preferred in type 1 and type 2 acetabular bone defects, while BSAPC should be preferred in type 3 and 4 defects.

The Dysplastic Hip: Not for the Shallow Surgeon

Patients who have hip dysplasia are often young and active. Hence, total hip replacement in this group needs meticulous planning to obtain satisfactory fixation with good long-term outcome. Acetabular reconstruction is often complex because of acetabular bone deficiency. Various techniques to deal with the deficiency of acetabular bone stock have been described, including cemented and cementless cups with or without bone graft, impaction bone grafting, perforating the medial acetabular wall (the cotyloplasty technique), and a small-diameter cup at elevated hip center. Multiple studies have reported long-term results of various techniques for acetabular reconstruction.

Cancellous Impaction Bone Grafting of Acetabular Defects in Complex Primary and Revision Total Hip Arthroplasty

The reconstruction of major acetabular bone defects during revision, conversion, and primary total hip arthroplasties (THAs) is challenging. We reviewed a consecutive series of 168 THAs (108 revisions, 8 conversions, and 52 primary THAs) performed by 1 surgeon (S.B.G.) between 1997 and 2008 using impaction bone grafting for acetabular reconstruction. Autograft, cancellous allograft croutons, and demineralized bone matrix were used to fill bone defects as needed. The acetabular bone deficiency was classified according to the American Academy of Orthopaedic Surgeons: type I, segmental deficiency with significant rim defect; type II, cavitary defects medially or posteriorly; type III, combined cavitary and segmental deficiency; type IV, pelvic discontinuity; and type V, arthrodesis. According to this method, 56 hips had type I, 31 hips had type II, 48 hips had type III, and 27 hips had type IV deficiencies. Of the 168 patients, 19 subsequently died of causes unrelated to the THA, and 11 were lost to follow-up. All patients had at least 2 years of follow-up. Average Harris Hip Score improved from 45.5±17.9 preoperatively to 81.1±16.5 postoperatively (P<.05) for revision THAs, from 40.0±11.3 preoperatively to 85.0±12.8 postoperatively (P<.05) for conversion THAs, and from 42.3±14.9 preoperatively to 85.0±12.0 postoperatively (P<.05) for primary THAs. All impaction grafted bone (allograft, autograft, or a combination) incorporated radiographically, thus restoring bone stock. Complications included 1 early infection, which was managed successfully with debridement and liner exchange, and 2 late infections that were managed successfully with staged revision. Two revisions required subsequent re-revision for late loosening. Two hip dislocations occurred, 1 of which required surgical treatment to place a constrained liner.

Femoral anteversion is correlated with acetabular version and coverage in Asian women with anterior and global deficient subgroups of hip dysplasia: a CT study

Morphological correlation between the acetabulum and femur at the hip joint is still controversial. We tested the hypothesis that femoral anteversion correlates with acetabular version and coverage in patients with developmental dysplasia of the hip (DDH). Using pelvic computed tomography (CT) images of 79 hips in 49 Asian women with DDH and 49 normal hips, we measured femoral anteversion, the axial and vertical acetabular version and the acetabular sector angle (ASA) to demarcate femoral head coverage. Depending on the location of the acetabular bone defect, dysplastic hips were divided into three subgroups: the anterior, global and posterior deficiency groups. We performed a comparative analysis between dysplastic and normal hips using the Wilcoxon rank sum test, and a relative analysis between femoral anteversion and acetabular measurements in dysplastic hips using Pearson's correlation coefficient. The amount of femoral anteversion in dysplastic hips was greater and more variable than in normal hips (p < 0.0001, p = 0.0277 respectively). Femoral anteversion in dysplastic hips correlated significantly with acetabular anteversion in the groups with anterior and global deficiency subgroups (p < 0.05, r = 0.2990, p < 0.05, r = 0.451 respectively), but not with the posterior deficiency subgroup. Femoral anteversion also correlated with vertical acetabular version. When acetabular coverage was examined, significant correlations were noted between femoral anteversion and anterior and superior coverage, but not with posterior coverage. These correlations were not observed in normal hips. Our results showed significantly greater and more variable femoral anteversion in DDH, and a significant correlation between femoral anteversion and acetabular version and coverage in DDH with anterior and global acetabular bone deficiency.

Bone Socket Deficiency: Allografts and Augments

Acetabular bone deficiency in revision total hip arthroplasty is one of the most technically demanding and difficult procedures for an orthopedic surgeon. Acetabular reconstruction for Paprosky type IIB, type IIIA, and type IIIB used to require bulk allograft for reconstruction. We currently are using trabecular metal augments to obtain biological ingrowth and support for reconstructing these defects.

Trabecular Metal Used for Major Bone Loss in Acetabular Hip Revision

The purpose of this study was to evaluate the outcome of trabecular metal (TM) acetabular components used in revision hip arthroplasty with major bone deficiency. We retrospectively reviewed the records of 46 patients undergoing revision hip arthroplasty with severe acetabular bone loss. Clinical outcomes were assessed using Harris Hip Score, Western Ontario and McMaster Universities, and Short-Form 12. Mean follow-up was 50 months. All patients had Paprosky type IIc or III acetabular bone deficiency. Major complications included 1 infection, 2 dislocations, and 1 arterial bleeding. Average Harris Hip Score was 78.2. Short-Form 12 scores were within population-based age-matched averages. Western Ontario and McMaster Universities scores were mainly in the 2 lowest disability categories. Porous tantalum shows promising results in revision arthroplasty with severe acetabular bone loss.

Impacted Autograft and Cementless Components in Acetabular Revision: A Retrospective Series

A retrospective review of the short- to medium-term results of acetabular revision using impacted autograft combined with cementless acetabular components is reported. Twenty-five cases with aseptic acetabular loosening and associated bone defects were revised using impacted autograft and a cementless acetabular component. Twenty-five patients were followed for a minimum of 4 years. Mean follow-up was 5.5 years (range 4.0-8.0 years). Radiographs showed that good incorporation of autograft occurred in all cases. Mean Harris hip score improved from 36.0 points (range 20.0 to 50.0) pre-operatively to 85.7 points (range 50.0 to 91.0) at latest follow-up. Outcome was Excellent in 8 cases, Good in 13 cases and Fair in 4 cases. No cases required further revision. The use of impacted autograft in combination with cementless components for acetabular revision can achieve good short- to medium-term result in patients with acetabular bone deficiency.

Quantitative Computerized Assessment of the Degree of Acetabular Bone Deficiency: Total radial Acetabular Bone Loss (TrABL)

A novel quantitative, computerized, and, therefore, highly objective method is presented to assess the degree of total radical acetabular bone loss. The method, which is abbreviated to “TrABL”, makes use of advanced 3D CT-based image processing and effective 3D anatomical reconstruction methodology. The output data consist of a ratio and a graph, which can both be used for direct comparison between specimens. A first dataset of twelve highly deficient hemipelves, mainly Paprosky types IIIB, is used as illustration. Although generalization of the findings will require further investigation on a larger population, it can be assumed that the presented method has the potential to facilitate the preoperative use of existing classifications and related decision schemes for treatment selection in complex revision cases.

Long-term Outcome of Shelf Grafts in Total Hip Arthroplasty for Developmental Hip Dysplasia

Primary total hip arthroplasty (THA) in patients with osteoarthrosis secondary to developmental hip dysplasia is often complex due to anterolateral acetabular bone deficiency. The use of femoral head (shelf) autograft during the index arthroplasty provides nonimmunogenic, osteoconductive support with the potential for enhanced bone stock should revision surgery be required. Few long-term studies document the outcome of the use of shelf grafts in primary THA or quantify the need for further bone graft at revision surgery. A retrospective analysis was conducted of a single surgeon's series of 31 THAs performed in 25 patients with developmental hip dysplasia. Postoperative biplanar radiographic analysis was performed at 3 and 6 months and annually thereafter for a mean of 14 years (range, 8-18 years). Grafts were assessed for union, resorption, and displacement. The need for acetabular bone graft at revision surgery was recorded. Bony union was observed in 93% of cases; fibrous union developed in the remaining 7%. There was no graft displacement. In 71% of cases, less than one-third of the graft had resorbed; one-third to one-half had resorbed in the remaining 29% of cases. Of 10 patients revised (all for loosening of the acetabular component), 2 required structural allograft for inadequate bone stock. Femoral head autograft allows effective acetabular coverage with excellent rates of union, exhibits minimal graft resorption in the long-term, and rarely requires further acetabular allograft in revision surgery.

Reconstruction of acetabular bone deficiency in total hip arthroplasty

To discuss the characteristics and reconstruction strategies of acetabular bone deficiency in total hip arthroplasty in order to find the optimal resolution for this clinical puzzle. Clinical and radiological materials of 37 patients (37 hips) with acetabular deficiency who underwent primary or revision total hip arthroplasty were analyzed retrospectively from May 1998 to August 2008. According to the common classification system for acetabular bone deficiency-the AAOS classification system, the acetabular bone defect was reconstructed using morselized or structural bone grafting, accessory acetabular hardware (ring, cup or cage) together with cemented or cementless acetabular component respectively. All patients were followed up regularly to assess their hip function improvement by measuring the Harris hip score and to find out the grafting bone healing, absorption and position of the prosthesis by plain radiographic examination. There were 11 primary and 26 revision total hip arthroplasty. There were 9 hips of AAOS-type I defect, 13 of type II and 15 of type III. Morselized bone grafting was used in 24 cases, bulk structural bone grafting in 6 cases and mixed bone grafting in 7 cases. Twenty-one patients used cementless prosthesis and 16 used cemented prosthesis. The average follow-up period was 53.7 months (6.5 to 130.5 months), the average preoperative Harris hip score was 42 +/- 8 with contrast to 87 +/- 5 of post-operation. Statistically significant difference was found according to t-test with P value less than 0.05. Major or complete healing of grafting bone was obtained at the latest follow-up. Acetabular bone defect during primary or revision total hip arthroplasty should be reconstructed according to its characteristics and severity. For relatively simple AAOS type I and type II cases, morselized or bulk structural bone grafting together with cementless prosthesis could achieve favorable initial stability, but for more severe AAOS type III cases, bulk structural bone grafting with accessory reinforcement hardware would be necessary. Though the early and mid-term results of the above strategies are satisfied, the long term outcome still require further study.

Total hip arthroplasty revision in elderly people with cement and Burch–Schneider anti-protrusio cage

Total hip arthroplasty revision is increasingly becoming a common procedure, but the acetabular bone loss and the advanced age of the patients make revision procedures extremely complex and technically demanding. The aim of the present work is to examine the clinical and radiological results of the Burch-Schneider anti-protrusio cage (APC) implanted in revision hip arthroplasty with severe acetabular bone deficiency in elderly people. Between February 1994 and November 2005, a total of 60 revision operations of acetabular components were performed in 60 select patients (42 females and 18 males), using the Burch-Schneider APC. The indication for the Burch-Schneider APC use was massive pelvic bone loss with migration of the prosthesis cup and high-grade acetabular defects (type III or IV AAOS). The mean age at the time of surgery was 82 years (range 78-85 years). Polymethylmetacrylate cement (PMMA) was used to fill bony deficiencies in all the procedures. No graft was used. The average Harris Hip Score had improved from 28.2 preoperatively to 82.5 points at the time of follow-up. According to the classification of Gill et al., we have seen no Burch-Schneider cages definitely loose or probably. Only one acetabular component has been revised (for recurrent dislocation). Acetabular reconstruction with the use of cement and an acetabular support ring appears to have a useful role in the treatment of severe acetabular bony deficiency in elderly patients and may provide a definitive reconstruction.

Anatomic and physiologic rationale for various technologies for primary total hip arthroplasty

A number of patients have anatomic or physiologic variations that may adversely affect the performance of a primary total hip arthroplasty. Various technologies have been utilized in an attempt to improve the outcomes for these patients; however, some of these potential solutions are controversial. The authors examined the complete body of literature for scientific evidence regarding the use of these new technologies. The anatomic and physiologic anomalies that were studied include extra-articular deformities, developmental dysplasia, Perthes disease, Type C femoral bone, acetabular bone deficiency, femoral rotational abnormalities, variations that increase the risk of hip dislocation, sickle cell anemia, and extremely small or large bone sizes. This article presents the current scientific evidence and imparts an unbiased view of the use of various technologies to provide individualized solutions for patients who have anatomic or physiologic variations.

Cement-free revision arthroplasty of the acetabulum--intermediate term outcome with trabecular-oriented acetabulum implant

In the case of hip revision arthroplasty, cementless implants combined with bone grafts are increasingly used to reconstruct the acetabular bone stock. The study on hand reports about the results with the trabecular orientated cup implant of CopflHolz after 10 years of application. A total of 256 hip revision arthroplasties were prospectively recorded with a mean follow-up period of 5.6 years. For the osseous augmentation of the acetabulum, autogenous bone was used in 227 cases, allogenic spongy bone in 15 cases and mixed bony materials in 8 cases. The clinical and radiological follow-ups were done after 3, 6, 12 months and then in 2-years intervals. Within the 10 years follow-up 3 rerevisions must be done because of deep infection, 6 rerevisions because of aseptic loosening or primary instable fixation. The specific failure rate of the used cup implant amounts to 96.2% five years after revision arthroplasty, and 86.8% ten years after revision arthroplasty. Revealed from a radiological point of view, the transplanted spongiosa showed in 83.5% a complete osseous integration one year after the operation. Worse incorporation was conspicuous especially when allografts or mixed bone grafts were used. Clinically, a permanent improvement of motion, pain and walking ability was seen postoperatively. 91% of all follow-up patients were satisfied with the result of the revision arthroplasty. The trabecular orientated cup implant has proven itself worthy for cementless cup revision arthroplasty and will be an alternative to the cups and rings used up to now for the reconstruction of great acetabular bone deficiencies.

The survival of support rings in complex acetabular revision surgery

Between 1980 and 2000, 63 support rings were used in the management of acetabular deficiency in a series of 60 patients, with a mean follow-up of 8.75 years (2 months to 23.8 years). There was a minimum five-year follow-up for successful reconstructions. The indication for revision surgery was aseptic loosening in 30 cases and infection in 33. All cases were Paprosky III defects; IIIA in 33 patients (52.4%) and IIIB in 30 (47.6%), including four with pelvic dissociation. A total of 26 patients (43.3%) have died since surgery, and 34 (56.7%) remain under clinical review. With acetabular revision for infection or aseptic loosening as the definition of failure, we report success in 53 (84%) of the reconstructions. A total of 12 failures (19%) required further surgery, four (6.3%) for aseptic loosening of the acetabular construct, six (9.5%) for recurrent infection and two (3.2%) for recurrent dislocation requiring captive components. Complications, seen in 11 patients (18.3%), included six femoral or sciatic neuropraxias which all resolved, one grade III heterotopic ossification, one on-table acetabular revision for instability, and three early post-operative dislocations managed by manipulation under anaesthesia, with no further instability. We recommend support rings and morcellised bone graft for significant acetabular bone deficiency that cannot be reconstructed using mesh.

Total Hip Arthroplasty in Patients with Bone Deficiency of the Acetabulum

Total hip replacement (THR) requires revision in only a minority of cases (approximately 17% of prosthetic hips fail), but when THR failures occur there may be significant acetabular bone deficiency. There is a variety of surgical hardware and strategies available to address this problem. The causes of primary THR revision include aseptic loosening or particle disease, infection, recurrent dislocation, implant failure, periprosthetic fracture, and leg length discrepancy. Almost all patients who need THR revision undergo a standard radiographic evaluation of the pelvis and hip. In general, CT is an excellent tool for evaluating loosening of the prosthesis caused by either mechanical reasons or infection, and MR imaging is best suited for evaluating the soft tissues surrounding the prosthesis. Nuclear medicine studies are performed when results of CT and MR imaging are inconclusive. When patients are evaluated for revision THR, radiologists must check for acetabular cup loosening, the amount and type of bone stock loss, the amount of component migration, and the presence or absence of liner wear. Before revision hardware is placed, bone stock loss must be repaired, either by using bone grafting or by placing accessory acetabular hardware such as cups, rings, or cages. The long-term success of revision acetabular surgery varies; there is acetabular cup presence at 5 years after surgery in 60%-94% of cases. Complications include postoperative infections, repeat liner wear, bone graft failure, periprosthetic or prosthetic fractures, dislocation, vascular injury, and nerve injury.

The Effectiveness of the Burch-Schneider Antiprotrusio Cage for Acetabular Bone Deficiency: Five to Twenty-one Years' Follow-up

From 1985 to 2001, the Burch-Schneider antiprotrusio cage (B-S APC) was implanted in 57 cases (55 patients) with massive acetabular deficiency. The B-S APC survived until the last review 5 to 21 years after operation in 89.5% of the cases, produced substantial pain relief, and increased range of hip motion and walking capacity. The 10.5% failure rate was due to aseptic loosening in 2 cases and mechanical failure in 4 cases. It appears that application of the B-S APC in extensive acetabular deficiency presents a durable solution provided that proper indications and technique are used.

Reconstruction of Major Segmental Acetabular Defects with an Oblong-Shaped Cementless Prosthesis: A Long-Term Outcomes Study

A retrospective outcomes study was performed on 25 consecutive acetabular reconstructions of major segmental defects by using an oblong-shaped cementless implant. All patients had combined acetabular defects (type III) as defined by the American Academy of Orthopaedic Surgeons classification of acetabular bone deficiency. Long-term follow-up was performed at an average of 11 years postoperatively. Clinical and radiographic outcomes were measured. Failures were defined by component revision or clear radiographic evidence of loosening. Six patients died before final evaluation, and 4 patients did not have complete radiographic data, leaving 14 patients (15 hips) for final analysis. At final follow-up, only 3 of the implants had failed and were revised. There was 1 case of a well-functioning implant with circumferential radiolucency; otherwise, there was no evidence of loosening among the remaining implants.

Acetabular revisions using a cementless oblong cup: five to ten year results

The purpose of this paper was to evaluate the results of acetabular revisions with the use of an oblong revision cup that is designed with its longitudinal diameter elongated relative to its transverse diameter. Between 1996 and 2001, 62 hips in 60 patients underwent an acetabular revision with the insertion of a LOR acetabular component. Seven hips were lost to follow-up or the patients died; the remaining 55 hips (53 patients) remained in follow-up for an average of 7.2 years (range: 5.0-10.1 years). One socket was revised for aseptic loosening, and another was operated on for a late polyethylene liner dissociation. The average Harris hip score (HHS) improved from 34 to 79. Results were rated as excellent in 16 hips, good in 28, fair in six and poor in three. Radiographic analysis demonstrated an improvement in the average vertical displacement of the hip centre: 49 hips had a well-fixed, bone-ingrown cup and four had a stable fibrous union. For large superolateral acetabular bone deficiencies, this implant facilitated a complex reconstruction without the need for bulk structural acetabular bone grafts, provided good clinical results and showed satisfactory stability at the midterm follow-up.